The present invention relates to syringe interfaces and, particularly, to syringe interfaces for use with syringes of variable size and to syringe drives including such syringe interfaces.
A number of injector-actuated syringes and powered injectors for use in medical procedures such as angiography, computed tomography, ultrasound and magnetic resonance imaging (MRI) have been developed. U.S. Pat. No. 4,006,736, for example, discloses an injector and syringe for injecting fluid into the vascular system of a human being or an animal. Typically, such injectors comprise drive members such as pistons that connect to a syringe plunger. For example, U.S. Pat. No. 4,677,980, the disclosure of which is incorporated herein by reference, discloses an angiographic injector and syringe wherein the drive member of the injector can be connected to, or disconnected from, the syringe plunger at any point along the travel path of the plunger via a releasable mechanism. A front-loading syringe and injector system is also disclosed in U.S. Pat. No. 5,383,858, the disclosure of which is incorporated herein by reference.
The front-loading injector of U.S. Pat. No. 5,383,858 includes a releasable mounting mechanism for securing the syringe to the front wall of the injector. Other types of releasable mounting mechanisms for front-loading syringes are disclosed in PCT International Patent Application PCT/US00/31991, filed Nov. 21, 2000, entitled Front Loading Medical Injector and Syringes, Syringe Interfaces, Syringe Adapters and Syringe Plungers for User Therewith, and U.S. patent application Ser. No. 09/448,484, filed Nov. 24, 1999, entitled Front Loading Medical Injector and Syringes, Syringe Interfaces, Syringe Adapters and Syringe Plungers for User Therewith, assigned to the assignee of the present invention, the disclosures of which are incorporated herein by reference
There is a need to use various size (e.g., volume) syringes in connection with powered injectors to best accommodate a procedure being performed on a particular patient. However, the use of specifically designed mounting mechanisms generally prevents the use of syringes of various types and/or sizes with front-loading injectors. Syringe adapters attachable to those front-loading injectors are sometimes used to allow the use of multiple syringes with the front-loading injectors. For example, U.S. Pat. No. 5,520,653 discloses several adapters designed to allow the use of various syringes with a front-loading injector. Other adapters for front-loading injectors are disclosed, for example, in U.S. patent application Ser. No. 09/365,285 filed Jul. 30, 1999 and in U.S. patent application Ser. No. 09/633,299 filed Aug. 8, 2000, assigned to the assignee of the present invention, the disclosures of which are incorporated herein by reference. Although adapters greatly facilitate the attachment of syringes of various types and sizes to a single injector or other syringe drive mechanism, manual installation of such adaptors absorbs valuable operator and injector time. Moreover, storage and tracking of multiple adapters can be a problem. It is also necessary for the operator to make injector program changes to insure that the proper flow characteristics are met for each of different syringe sizes.
An injector can also include a multi-position turret that can be moved from one position to the another position to mount multiple syringes. An injector having a two-position turret is disclosed, for example, in U.S. Pat. No. 4,006,736. In such injectors, the user must physically change the position of the mechanical turret to accommodate different syringes. Moreover, the injector must be programmed by the user for the two different syringes
Other injectors use the same interface for syringes of different volume but such syringes must be of the same diameter and of different length. A smaller volume syringe in such a system will have the same inherent accuracy problems as a larger volume syringe. Such a system may not be suitable, for example, for use with pediatric patients where very small volumes are injected.
It is very desirable to develop syringe interfaces that can be used with syringes of various size to facilitate attachment of such syringes to injectors, loaders and other devices in connection with which syringes are used.